A tale of ambition and overreach.
“At the age of six I wanted to be a cook. At seven I wanted to be Napoleon. And my ambition has been growing steadily ever since.”
André Citroën, the French industrial giant, may not have possessed a level of ambition quite as extreme as that claimed by the controversial Spanish artist, but few amongst his peers in the automobile industry could match his boundless energy and determination to lead the way, often eschewing received wisdom and conventional thinking in the process. These attributes brought him fame and fortune, but would also eventually prove to be his undoing.
A salient example of the double-edged sword of Citroën’s ambition and overreach was the Traction Avant of 1934. It was a revolutionary, highly modern and accomplished design in almost every possible way. Citroën’s original plan was for the Traction to be equipped with a newly designed fully automatic transmission, the brainchild of a prolific Brazilian inventor. That plan had to be abandoned so, notwithstanding its long list of innovations in both engineering and construction, the Traction would be saddled with an archaic three-speed manual gearbox for the duration of its long career. Not only was its three-speed configuration(1) increasingly perceived as antiquated as time moved on, it was also baulky in operation, noisy and, in early Tractions, prone to failure as well.
The reason for this unhappy compromise was that the manual gearbox had to be developed in a rushed last-minute programme and made to fit in the housing designed for an automatic transmission that never passed the prototype stage and was finally abandoned only weeks before the Traction’s introduction.
Dimitri Sensaud de Lavaud was born in Valladolid, Spain in 1882, but became a naturalised Brazilian in his youth. His father was French and his mother Russian, which explains his unusual combination of given and family names. Dimitri’s father, Baron Evariste Sensaud De Lavaud, operated a ceramic pipe factory in Osasco, Brazil, to where his family had emigrated from Spain.
As a teenager, Dimitri demonstrated a precocious talent for engineering when he invented a machine using a centrifugal casting process that he claimed would greatly improve the production efficiency of his father’s factory. The elder Sensaud de Lavaud was not immediately convinced, but agreed to try it out and pay his son royalties if it worked. It did, and when Dimitri’s machines were sold to other factories, it was not long before the son became wealthier than his father.
In the early twentieth century, Dimitri moved to the USA where he marketed his centrifual casting process with great success. By the time he moved again in 1920, this time to France, he was a very rich man. Having amassed a fortune large enough never to have to work or worry again, Dimitri indulged his creative passions by inventing.
Dimitri was fascinated by both aviation(2) and the automobile, two fields of engineering that were still in their early stages of development, so offered great potential for an inventor. At the 1927 Paris Salon de L’Automobile, Dimitri presented a car of his own design. Apart from the absence of running boards, the outward appearance of the Labourdette-bodied vehicle was, at first acquaintance, pleasingly proportioned but quite conventional.
A separately displayed bare chassis proved that one should never judge a book by its cover, however. Made of Alpax, an aluminium-silicon alloy, the naked chassis allowed the mechanically inclined to admire the hydraulic brakes and independent suspension on all four wheels. According to its constructor, the ‘springless suspension’ by rubber cushions was completely maintenance-free.
Up front was a 5.5-litre inline six-cylinder engine made by the American firm, Continental. It was a proven powerplant, but nothing to get excited about. The car’s real innovation was the manner in which drive was transmitted to the rear wheels via a continuously variable fully automatic transmission. This was a complex and intricate piece of engineering, providing automatic drive through a system of oscillating plateaus(3).
This transmission was quite different from the one that might have been used in the Traction, which was still some years away. Offered for just three years, the expensive Sensaud De Lavaud car found few buyers, but those who knew the man confided that, for him, that never seemed to be the point: as soon as he had realised an idea, he did not appear to be very motivated to monetize it, but rather moved on to new technological challenges(4). In 1925, Sensaud de Lavaud was awarded the Knight’s Cross of the Legion Of Honour by the Academy of Sciences in Paris in recognition of the value of his engineering research.
Around 1930, Sensaud de Lavaud first got in touch with Citroën and, two years later, the manufacturer’s Bureau d’Etudes equipped two Citroëns, a C4 and a C6, with his hydraulic automatic transmission for testing purposes. This new transmission was named ‘Turbine’ by the Brazilian inventor who stated in a surviving technical memo: “The engine directly drives two wheels with 318 blades stirring oil in a sealed crankcase. This oil hits fins connected to the transmission shaft, and by adjusting the speed of the engine by ratio to the slope or resistance of the road we obtain, before reaching the direct grip, an infinite range of speeds, of absolute flexibility”.
During one of the test runs, André Citroën himself took the wheel and was impressed: not only were progress and acceleration extremely smooth, the transmission ironed out the last remaining vibrations transmitted by the ‘Moteur Flottant’(5) rubber engine mounts. It is not difficult to imagine Citroën seeing it as the ideal transmission for the revolutionary front-wheel-drive car he was planning to introduce.
The Bureau d’Etudes noted that there were some negatives, however. Acceleration, while smooth, was quite leisurely, fuel consumption was noticeably higher than with a manual gearbox, production costs were substantial and, most seriously, the Turbine had a worrying tendency to overheat its transmission oil on sustained inclines.
It has at times been suggested that André Citroën, blinded by the potential and novelty of Sensaud de Lavaud’s Turbine, decided right there and then that it would be fitted to all Tractions by 1934. The exclusive contract with Sensaud de Lavaud was, however, only signed on 17th november 1933, well over a year after Citroën’s test drive.
A lot of further fettling and testing took place, but the overheating problem persisted. André Citroën reacted in characteristic fashion to doubts and criticisms concerning the problems with the newfangled transmission raised by none other than André Lefebvre: “You are the engineer, you solve them!”. In light of this, it is interesting to remember that Lefebvre had worked at Voisin before coming to Citroën (via a short and unhappy stint at Renault). Some Voisin models had been equipped with the earlier automatic transmission design by Sensaud de Lavaud(6) and similar problems had arisen that even the talented and resourceful Lefebvre was unable to solve.
At the conclusion of yet another failed test, Lefebvre quipped to a fellow engineer: “Do you like fries? Just put some potatoes inside the transmission- they will be nice and crispy by the time you reach the top of the hill at Meudon”. For many others at the Bureau d’Etudes, the fragile and temperamental automatic transmission only increased the complexity of what was already a car full of new ideas that was being developed in record time. Doubts and objections were likely discussed within the Bureau d’Etudes, but all were, of course, aware whose name was above the entrance to the Quai de Javel plant.
From January 1934 onwards, Traction Avants were produced without transmissions or driveshafts in anticipation of receiving those later. Soon, their storage created logistical problems within the factory.
A month later, during a large meeting presided over by André Citroën on the progress of the Traction, Charles Brull, one the company’s most highly respected engineers, threatened to resign if the Turbine was not fixed or abandoned. André Citroën finally gave in (something not exactly typical of the man) and postponed the release date of the Traction to give his engineers one more shot at getting Sensaud de Lavaud’s transmission production-ready. It was all to no avail and, after a final test with Pierre Michelin and Lefebvre where only one of the five cars in the convoy was able to make it back to the factory, it was clear that the Turbine could simply not be used in the forthcoming Traction.
(In the photos above, notice the much smaller shift lever of the Turbine (left and bottom left); in the second photo the engine bay on top is a rare image of a Turbine-equipped Traction pre-production car as it does not have the long connecting rods to the gearbox as seen in the bottom photograph.)
André Citroën finally had to face the facts, and instructed the Bureau d’Etudes to design and build a conventional manual gearbox for the Traction. Not unexpectedly, his engineering team had seen this coming and had already commenced development of just that in secret. Camusat, the Bureau d’Etudes’ transmission wizard, designed a thoroughly conventional three-speed gearbox in a very short time. This was all the more impressive as he was at the time recovering from an accident and his arms were in bandages and plaster.
Lefebvre himself designed the unusual gear linkage system, with long rods connecting the gearshift lever to the gearbox which sat in front of the engine. Its strange appearance soon earned it the nickname ‘Eiffel tower’. Just two weeks after the Turbine was axed, the first Tractions with the manual three-speed box were already undergoing test trials.
Interestingly, testing and development of the Sensaud de Lavaud transmission continued until mid-november 1934, just weeks before André Citroën was forced to file for bankruptcy and hand over the reins of his company to Michelin. It appears that there was still the belief, but possibly held only by André Citroën and Dimitri Sensaud de Lavaud, that the Turbine could be made to work reliably and introduced at a later date. It would not be until 1948, however, that Buick would succesfully introduce its Dynaflow transmission, which functioned along similar lines .
On 18th April 1934, the Traction was oficially presented to the press after a staggeringly short development time of just over thirteen months. A large part of the credit for this achievement must go to Lefebvre, who was an extraordinarily gifted engineer as well as quick thinker, but who could also motivate those around him. It also helped that Lefebvre was spared by André Citroën personally from time-consuming and distracting administrative duties.
The whole Bureau d’Etudes staff worked extremely hard, many even giving up their usual summer holidays and often working seven days a week. The Traction Avant itself was so promising and revolutionary that all who worked on it believed in its concept and went the extra mile. By the same token, the fact that most were acutely aware that the future of the company depended on the success of this car motivated them to do everything they could to make it succeed.
Sadly, André Citroën never witnessed his Traction coming good, dying from stomach cancer in July 1935. The first Tractions had their share of problems, especially with the gearbox and homokinetic driveshafts. Within a short time, however, most(7) issues were fixed and the car became a much loved presence on the streets and autoroutes in France and many other countries. The Traction Avant enjoyed a 23-year long career, changing very little during its lifetime, hence proving the essential ‘rightness’ of its concept.
(1) Despite incessant requests from customers for a fourth gear to be added, Citroën never did, prompting enterprising outside suppliers to offer four-speed gearboxes of their own design for the Traction.
(2) On 7th January 1910, Dimitri Sensaud de Lavaud was the pilot of the first controlled powered flight in Latin America. He had personally designed and built the airplane, including its engine.
(3) A technical explanation of ‘oscillating plateaus’ would be much appreciated, if any of our readers could oblige.
(4) Over his lifetime, Sensaud de Lavaud would be granted patents for around 250 inventions.
(5) A Chrysler invention produced under license by Citroën.
(6) Sensaud de Lavaud’s first automatic transmission had been fitted to some Voisins in 1925 but, as that was very much an upmarket car, its technical delicacies were not widely known to the public. It would also be applied in the prestigious but ill-fated Bucciali in 1928.
Sensaud de Lavaud was not the first to come up with the basic idea: The first torque converter was patented as a propeller shaft reducer in 1904 and built in 1908 by German engineer, Hermann Föttinger. In 1914, the German battlecruiser ‘Wiesbaden’ was fitted with two hydraulic converters of his design.
(7) As mentioned earlier, the Traction’s manual gearbox would continue to be the car’s Achilles’ heel. The reliability problems were resolved, but it remained a crude device, unworthy of the Traction Avant.